<template>
  <!-- 商品分类导航 -->
  <div class="type-nav">
    <!-- 当鼠标进入和离开时，能够显示或隐藏列表 -->
    <div class="container">
      <div @mouseenter="enterShow" @mouseleave="leaveShow">
        <h2 class="all">全部商品分类</h2>

        <!-- 过渡动画 -->
        <transition name="sort">
          <!-- v-show="show",判断是否隐藏 -->
          <div class="sort" v-show="show">
            <!--  利用事件委派和编程式导航实现路由的跳转与传参 -->
            <div class="all-sort-list2" @click="goSearch">
              <!-- 一级分类 -->
              <div
                class="item bo"
                v-for="c1 in categoryList"
                :key="c1.categoryId"
              >
                <h3>
                  <a
                    :data-categoryName="c1.categoryName"
                    :data-category1Id="c1.categoryId"
                    >{{ c1.categoryName }}</a
                  >
                  <!-- <router-link to="/Search">{{c1.categoryName}}</router-link> -->
                </h3>

                <!-- 二级、三级分类 -->
                <div class="item-list clearfix">
                  <div
                    class="subitem"
                    v-for="c2 in c1.categoryChild"
                    :key="c2.categoryId"
                  >
                    <dl class="fore">
                      <dt>
                        <!-- <router-link to="">{{c2.categoryName}}</router-link> -->
                        <a
                          :data-categoryName="c2.categoryName"
                          :data-category2Id="c2.categoryId"
                          >{{ c2.categoryName }}</a
                        >
                      </dt>
                      <dd>
                        <em v-for="c3 in c2.categoryChild" :key="c3.categoryId">
                          <!-- <router-link to="">{{c3.categoryName}}</router-link> -->
                          <a
                            :data-categoryName="c3.categoryName"
                            :data-category3Id="c3.categoryId"
                            >{{ c3.categoryName }}</a
                          >
                        </em>
                      </dd>
                    </dl>
                  </div>
                </div>
              </div>
            </div>
          </div>
        </transition>
      </div>
      <nav class="nav">
        <a href="###">服装城</a>
        <a href="###">美妆馆</a>
        <a href="###">尚品汇超市</a>
        <a href="###">全球购</a>
        <a href="###">闪购</a>
        <a href="###">团购</a>
        <a href="###">有趣</a>
        <a href="###">秒杀</a>
      </nav>
    </div>
  </div>
</template>

<script>
import { mapState } from "vuex";
// import router from 'vue-router'
/* //引入lodash,完成防抖和节流的功能
import _ from 'lodash';
console.log(_); */
export default {
  name: "TypeNav",
  data() {
    return {
      show: true,
    };
  },

  //组件挂载完毕，可以像服务器发送请求
  methods: {
    // 进行路由跳转的方法
    goSearch(event) {
      //把子节点当中a标签，在加上自定义属性 :data-categoryName  ，其余子节点是没有自定义属性的
      let element = event.target;

      //获取到当前触发这个事件的子节点当中带有自定义属性的这样一个节点，此节点一定是a标签
      // 节点中有一个dataset属性，可以获取节点的自定义属性和属性值
      let { categoryname, category1id, category2id, category3id } =
        element.dataset;
      if (categoryname) {
        //整理路由跳转的参数
        let location = { name: "Search" };
        let query = { categoryName: categoryname };
        // let params = {keyword:this.$route.params}
        if (category1id) {
          query.category1Id = category1id;
        } else if (category2id) {
          query.category2Id = category2id;
        } else {
          query.category3Id = category3id;
        }
        //整理参数
        location.query = query; //标签进入的
        // location.params=params;
        if (this.$route.params.keyword) {
          location.params = this.$route.params;
        }
        //路由跳转
        this.$router.push(
          location,
          () => {},
          () => {}
        );
      }
    },
    enterShow() {
      this.show = true;
    },
    leaveShow() {
      if (this.$route.fullPath != "/Home") {
        this.show = false;
      }
    },
  },
  mounted() {
    //通知Vuex发送请求，获取数据，存储与仓库当中
    //调用$store下的actions的categoryList方法，通知Vuex发送请求获取数据
    // this.$store.dispatch("categoryList");  //这段放到app上，这样就能做到只调用一次服务器
    // console.log(this.$store);
    //判断路由是否为Home，如果不是，则将TypeNav下拉界面隐藏
    if (this.$route.fullPath != "/Home") {
      this.show = false;
    }
  },
  computed: {
    ...mapState({
      categoryList: (state) => state.home.categoryList,
    }),
  },
};
</script>

<style scoped lang="less">
.type-nav {
  border-bottom: 2px solid #e1251b;

  .container {
    width: 1200px;
    margin: 0 auto;
    display: flex;
    position: relative;

    .all {
      width: 210px;
      height: 45px;
      background-color: #e1251b;
      line-height: 45px;
      text-align: center;
      color: #fff;
      font-size: 14px;
      font-weight: bold;
    }

    .nav {
      a {
        height: 45px;
        margin: 0 22px;
        line-height: 45px;
        font-size: 16px;
        color: #333;
      }
    }

    .sort {
      position: absolute;
      left: 0;
      top: 45px;
      width: 210px;
      height: 461px;
      position: absolute;
      background: #fafafa;
      z-index: 999;

      .all-sort-list2 {
        .item {
          h3:hover {
            background: #ef645c;
          }
          h3 {
            line-height: 27px;
            font-size: 14px;
            font-weight: 400;
            overflow: hidden;
            padding: 0 20px;
            margin: 0;

            a {
              color: #333;
            }
          }

          .item-list {
            display: none;
            position: absolute;
            width: 734px;
            min-height: 460px;
            background: #f7f7f7;
            left: 210px;
            border: 1px solid #ddd;
            top: 0;
            z-index: 9999 !important;

            .subitem {
              float: left;
              width: 650px;
              padding: 0 4px 0 8px;

              dl {
                border-top: 1px solid #eee;
                padding: 6px 0;
                overflow: hidden;
                zoom: 1;

                &.fore {
                  border-top: 0;
                }

                dt {
                  float: left;
                  width: 54px;
                  line-height: 22px;
                  text-align: right;
                  padding: 3px 6px 0 0;
                  font-weight: 700;
                }

                dd {
                  float: left;
                  width: 415px;
                  padding: 3px 0 0;
                  overflow: hidden;

                  em {
                    float: left;
                    height: 14px;
                    line-height: 14px;
                    padding: 0 8px;
                    margin-top: 5px;
                    border-left: 1px solid #ccc;
                  }
                }
              }
            }
          }

          &:hover {
            .item-list {
              display: block;
            }
          }
        }
      }
    }
    //过渡动画的样式
    .sort-enter {
      height: 0px;
    }
    // .sort-enter-to{}
  }
}
</style>